1. Field of the Invention
The present invention relates to cleaning devices, more particularly to a cleaning device for use in an image forming apparatus for forming a toner image on a printing medium.
2. Description of Related Art
As an invention related to a conventional cleaning device, a cleaning device described in, for example, Japanese Patent Laid-Open Publication No. 2007-334011 is known. FIG. 21 is a configuration diagram of the cleaning device 500 described in Japanese Patent Laid-Open Publication No. 2007-334011.
The cleaning device 500 is adapted to collect toner adhering to a secondary transfer roller 504, and includes a fur brush 506, a metal roller 508, and a cleaning blade 510, as shown in FIG. 21. The fur brush 506 is disposed in contact with the secondary transfer roller 504 so as to gather toner adhering to the secondary transfer roller 504.
The metal roller 508 is disposed in contact with the fur brush 506, and when a predetermined voltage is applied thereto, the metal roller 508 collects the toner gathered from the secondary transfer roller 504 by the fur brush 506. The cleaning blade 510 separates the toner from the surface of the metal roller 508. Thus, the secondary transfer roller 504 is cleaned.
However, in the cleaning device 500, toner on the fur brush 506 might readhere to the secondary transfer roller 504. More specifically, the metal roller 508 collects toner adhering to the fur brush 506. However, some of the toner remains on the fur brush 506 without being collected by the metal roller 508. The remaining toner is carried to the interface between the secondary transfer roller 504 and the fur brush 506 through rotation of the fur brush 506. Thereafter, due to the impact of the fur brush 506 contacting the secondary transfer roller 504, centrifugal force created by rotation of the fur brush 506, etc., the toner moves from the fur brush 506 to the secondary transfer roller 504, and readheres to the secondary transfer roller 504. Such toner readhesion might stain the back of a sheet of paper and deteriorate toner image quality.